Use your eyes.
If you need the definitive guide to spotting and dodging nefarious drones, then look no further than this US Army manual on counter unmanned aircraft systems (UAS) techniques.
Facing threats from non-state actors such as ISIS, which are perpetually bombarding coalition forces with DIY consumer drones, to possibly fighting against swarms of state-deployed drones in near-future battlefields, the US military has thought it's time to start training its soldiers on how to deal with the problem.
And the main gist of the manual seems to be: "Just look for them, dude."
Published in April, Counter-Unmanned Aircraft System Techniques , dutifully spotted by Steven Aftergood writing for the Federation of American Scientists , describes in great detail how Army units—ranging from a brigade, to battalion, to company level—should detect, identify, and defeat what the Army designates LSS (low, slow, and small) drones.
One illustrated tactic is the deployment of 'air guards', essentially observer personnel who should "establish positions within visual range" of their own unit and "be equipped with the necessary optical gear to perform search and scan techniques to reduce the enemy's ability to evade detection."
The visual scanning, if you need to train in your own back yard, looks something like this, ensuring the observer can see, hear and report any drones:
The US Army is, however, working on more technological methods of fighting drones. Earlier this month, the Army announced it had upgraded its Stryker-mounted laser to a power of 5kW—a power capable of knocking out drones. A flurry of contracts have also been signed over recent months relating to drone detection systems.
But as the Army acknowledges in its latest manual, small drones are a tricky adversary. "Integrated air and missile defense (IAMD) capabilities can effectively counter larger classes of UAS but have difficulty tracking, identifying, and defeating LSS UAS," the guide advises. "Small units operating in and around combat areas should assume they are being observed by the enemy and not assume they are under the umbrella (protection) of air and missile defense units."
The Army even admitted in a late-2016 counter-drone document that there is no single, comprehensive solution to the UAS problem. Looks like the world's miltiaries are digging in for the long haul then. Drones are on the battlefield and they're not going anywhere soon.
Subscribe to Science Solved It, Motherboard's new show about the greatest mysteries that were solved by science.